Phillies general manager Ruben Amaro Jr. sounds like a man with something up his sleeve.

Maybe something small, he said Wednesday.

Amaro is actively trying to add an outfielder before spring training. He gave off the impression that hes on the trail of something, but would not name names.

It would likely come from outside the organization, Amaro said. It could be a trade, but probably a free agent.

Amaro was asked if the outfielder he was pursuing would come on a minor-league deal or a big-league deal.

Not sure, he said. But were hopeful of adding an outfielder.

Michael Bourn is the top outfielder remaining on the free-agent market, but the Phillies, having traded for centerfielder Ben Revere, dont appear to be in on him. The Phils like Scott Hairston, but not his price tag. If it comes down, he could be a fit. The remainder of the free-agent outfield class is not pretty. Delmon Young is out there, but hes a defensive liability and has had off-field issues. Juan Rivera, Bobby Abreu, Ben Francisco, Ryan Sweeney, Ryan Raburn and Rick Ankiel also remain as free agents.

Amaro was asked to rate his chances of adding an outfielder as high or low.

Medium, he said.

The Phillies have considered trading for Alfonso Soriano or Vernon Wells. They could revisit those ideas down the road. Arizona's Justin Upton is also available for trade. Sources say the Phillies have investigated the possibility of acquiring Upton, but are wary of Arizona's sky-high asking price.

Were not done building our team, Amaro said. Our job of improving the team is never done.

The Phillies have shown that by adding pitching inventory in recent days. They have signed veteran starters Rodrigo Lopez and Aaron Cook to minor-league deals. Veteran reliever Juan Cruz was also signed to a minor-league deal. All three have been invited to big-league camp and will get a shot to make the roster.

Lopez is 37. Cook turns 34 in February. Cruz is 34.

The Phillies have some health concerns in their starting rotation. Roy Halladay spent time on the DL with shoulder issues last season and Cole Hamels dealt with shoulder soreness late last season and again early this offseason. Amaro was asked if he signed Lopez and Cook because of those concerns.

No, he said. Were just trying to protect ourselves as much as we can. The more depth we have the better. This gives us veteran guys so if someone goes down we dont have to force our young guys. Its also possible they could help in the bullpen. Anytime you can get depth without a huge financial commitment its a plus. And it creates a little competition, which is good.

Lopez will get 1 million if he makes the club. Fox Sports reports that Cooks deal is worth 1.6 million if hes in the majors. Cook, who has battled injuries in his career, hasnt had an ERA below 5.00 since 2009.

Halladay has been throwing in Florida. Amaro said the reports were good. Halladay is expected to begin throwing off a mound the last week of January. Spring training begins Feb. 12.